Reporting and representation of participant race and ethnicity in phase III clinical trials for solid tumors.

Background: Including racial and ethnic minorities in clinical trials is essential for advancing health equity. Despite progress, trials often do not mirror patient population demographics.

Methods: The National Library of Medicine's Clinical Trials database was queried for phase III trials of lung, colorectal, breast, and prostate cancers. A reference population was identified from the Surveillance, Epidemiology, and End Result (SEER) database, covering 48% of the US population.

Results: Among 181 trials, race and ethnicity data were included in 86.7% and 60.2% of trials, respectively, with improving reporting over time. Participants were predominantly White (76.3%), followed by Asian/Pacific Islander (14.1%), Black/African American (4.5%), and American Indian/Alaska Native (0.6%). Hispanic/Latino constituted 6.4% of participants. The proportion of non-White groups increased from 19.4% in trials started before 2011 to 26.2% after 2015. Compared with SEER data, the percentages were lower for Asian/Pacific Islander across all cancers, Black/African American in breast and prostate cancers, American Indian or Alaska Native in colorectal, breast, and prostate cancers in US solely trials.

Conclusions: Reporting and enrollment of racial and ethnic minorities in trials remain inadequate but improving. To enhance diversity, real-world data are warranted to identify recruitment goals by better assessing the geographic distribution within the patient population.